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Academic Year 2016- 2017 Third Term Science Revision Sheets SCIENCE Name: Date: Grade

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Academic Year 2016- 2017 Third Term Science Revision Sheets SCIENCE Name: Date: Grade Academic Year 2016- 2017 Third Term Science Revision sheets SCIENCE Name: ________________________ Date: _______________ Grade:6 Section: _____________ Q1: Choose the letter of the choice that best answer the questions: 1. How can the speed of a mechanical wave be calculated? A. Add the wavelength and the period. B. Divide the period by the wavelength. C. Divide the wavelength by the period. D. Multiply the wavelength and the period. 2. What is one way that electromagnetic waves differ from mechanical waves? A. Electromagnetic waves move slower. B. Electromagnetic waves are longitudinal. C. Electromagnetic waves can travel through empty space. D. There is no difference between electromagnetic and mechanical waves. 3. What is the name of the lowest point of a wave? A. crest B. trough C. amplitude D. rest position 4. Astronomers study radio waves to learn about the universe. Why might radio waves be used to study objects in space? lesson quiz A. They are sound waves that cause vibrations in stars and planets. B. They are electromagnetic waves, so they don’t require a medium. C. They are mechanical waves that pass through interstellar particles. D. They are longitudinal waves, which create compressions in the fabric of space. 5. Which is the best description of a wave? A. energy that makes particles move B. a disturbance that transfers energy C. a disruption causing the transfer of matter D. any type of matter that vibrates back and forth 6. A wave produced by an earthquake appears in the diagram below: A second wave leaves the center of an earthquake at the same time. The second wave is a longitudinal wave. After 10 seconds, will the two waves travel the same distance? A. Yes, because both waves are longitudinal waves. B. Yes, because all waves travel at the same speed in similar mediums. C. No, because only one type of wave can travel through a medium at a time. D. No, because transverse waves travel at different speeds than longitudinal waves. 7. A whale makes a noise underwater that is too low-pitched for humans to hear. What type of wave is this? A. S wave B. visible light C. mechanical D. electromagnetic 8. The speed of a mechanical wave through lesson 2 a medium depends on the type of medium. It also depends on the type of mechanical wave. Which statement is true? A. All waves travel at the same speed through any medium. B. All waves travel at the same speed if no medium is present. C. Electromagnetic waves require a medium, but mechanical waves do not. D. Mechanical waves require a medium, but electromagnetic waves do not. 9. The diagram below shows a wave pattern. One wave property that is shown is amplitude. Amplitude is the vertical distance from the rest position to either the crest or the trough of a wave. What is the rest position of a wave in the diagram? A. E B. F C. distance from G to H D. point that is halfway between G and H 10. Brianna reported a measurement in units of hertz. What property of a wave was she measuring? A. period B. frequency C. amplitude D. wavelength 11. During a thunderstorm, Sanjay saw lightning and then heard thunder 5 seconds later. What would be different if the air had been warmer? A. He would have seen the lightning and heard the thunder at the same time. B. He would have heard the thunder before seeing the lightning. C. He would have heard the thunder sooner. D. He would have heard the thunder later. 12. Aimee and Patrick are playing hide-and-seek on a summer day. Aimee gives Patrick a clue to her location by knocking three times every 30 seconds. Which characteristic of waves makes this a useful clue to help Patrick find Aimee? A. Wave energy increases with distance. B. Wave energy decreases with distance. C. Sound waves travel faster in cold air than in warm air. D. Sound waves travel faster in warm air than in cold air. 13. Which statement best describes how humans hear sound? A. Sound waves enter the ear canal and increase in amplitude, which causes you to hear the sound. B. Sound waves cause parts of the ear to vibrate until the waves are converted to electrical signals, which are sent to the brain. C. Sound waves travel into people ears, and then the eardrum sends the sound waves to the brain. D. Sound waves become sounds when they strike the eardrum inside the ear. 14. When Consuelo struck a tuning fork and held it close to a string on a guitar, the string began to vibrate on its own and make a sound. Which statement best explains why the string vibrated without anyone touching it? A. The string vibrated because of destructive inference between its sound waves and those of the tuning fork. B. The tuning fork produced ultrasonic frequencies beyond human hearing. C. The tuning fork and the guitar string both created mechanical waves. D. The string vibrated because of resonance, which happened because the tuning fork and guitar string have the same natural frequency. 15. The diagram below shows a sound wave traveling through a medium. Which statement best describes how the sound wave is moving through a medium? A. The sound wave is creating tensions and accumulations in the medium. B. The sound wave is creating an echo inside the medium. C. The sound wave is creating compressions and rarefactions in the medium. D. The sound wave is creating a mechanical wave in the medium. 16. Which material best absorbs sound waves in a room? A. heavy curtains B. brick walls C. hardwood floors D. cement floors 17. Yorgos drew a diagram of a wave and labeled its parts, as shown below. Wavelength is typically measured between the crests to two successive waves. Which labels represent a crest and a wavelength? A. G points to a crest, F is a wavelength B. G points to a crest, E is a wavelength C. H points to a crest, E is a wavelength D. H points to a crest, F is a wavelength 18. Which of the following is not a way in which echolocation is used? A. flying bats avoiding trees and houses at night B. sending messages over telephone lines C. dolphins finding fish in deep water D. mapping the ocean floor 19. Josh observed a bolt of lightning during a thunderstorm. It took more than 15 seconds for Josh to hear the sound of thunder. Why did Josh see the lightning strike before he heard the thunder? A. Thunder always takes 15 seconds to travel through the air after lightning strikes. B. Light waves from the lightning and sound waves from the thunder moved through different media. C. Light waves are electromagnetic waves that travel much faster than mechanical waves, such as the sound waves he heard as thunder. D. The conditions in the air at the time allowed light waves to move faster than the sound waves he heard as thunder. 20. The diagram below shows the distribution of particles in two different kinds of media. Liquid Gas Which statement best compares how sound waves travel through the media shown above? A. Sound waves travel at the same speed through both of the media shown. B. Sound waves move faster through the liquid medium on the left than the gaseous medium on the right. C. Sound waves move faster through the gaseous medium on the right than the liquid medium on the left. D. Sound waves cannot travel through either medium that is shown above. 21. Suppose a mechanical wave is traveling through medium A. When the wave enters medium B, it speeds up. Which of the following statements can be true about medium A and medium B? A. Medium A is a solid and medium B is a gas. B. Medium A is a liquid and medium B is a solid. C. Medium A is a gas and medium B is a vacuum. D. Medium A is a vacuum and medium B is a liquid. 22. What is the term for the distance from the highest part of one wave to the highest part of the next wave? A. period B. frequency C. amplitude D. wavelength 23. Caleb is at the beach. He counts the number of wave peaks that pass a given point on the beach in a certain amount of time. What property of waves does Caleb measure? A. speed B. frequency C. amplitude D. wavelength 24. Carlos is studying electromagnetic waves. He finds a diagram of the electromagnetic spectrum shown below, but it is missing a label. What is the proper label of the unlabeled region? A. radar B. television C. visible light D. cosmic rays 25. An earthquake sends out mechanical waves in all directions from its source. In answering the following question, assume the wave starts carrying energy equally in all directions. The wavefront reaches each of the different locations as shown in the diagram. At which location does a point on the wavefront have the least energy? A. 1 B. 2 C. 3 D. 4 26. In which direction do longitudinal waves travel? A. They travel in random directions. B. They travel around in a circular motion. C. They travel parallel to the direction of the disturbance. D. They travel perpendicular to the direction of the disturbance. 27. Through which medium does a mechanical wave travel most quickly? A. solid B. liquid C. less dense gas D. very dense gas 28. What is the speed of a wave with a wavelength of 4 cm and a frequency of 8 hertz? A.
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